Electrochemical biosensors are known. They have been used to determine the concentration of various analytes from biological samples, particularly from blood. Biosensors are described in U.S. Pat. Nos. 5,413,690; 5,762,770; 5,798,031; and 5,997,817, the disclosure of each of which are hereby incorporated by reference. Laser ablation is a known technique the uses a laser to remove a material. See, for example, U.S. Pat. Nos. 5,576,073 and 5,593,739, the disclosure of each of which is expressly incorporated herein by reference. Such known laser ablation systems use a high power excimer laser, such as a krypton fluoride excimer laser with an illumination wavelength of 248 nanometers, to remove surface material. Die cutting processes have been also used to form reagent wells that include walls that hold or retain liquid reagents on the sensor strip in place while they dry. See, for example, U.S. Pat. Nos. 4,225,410 and 5,288,636.
According to the present invention a biosensor is provided. The biosensor comprises a plate element formed to include a pre-determined reaction zone and a recess positioned adjacent to the reaction zone. In addition, the biosensor comprises a reagent positioned on at least a portion of the reaction zone.
According to another aspect of the present invention, a biosensor is provided that comprises a bottom plate element including a first surface formed to include a recess therein, a reagent positioned on the first surface, and a top plate element coupled to the bottom plate element. In addition, the reagent covers at least a portion of the recess.
Still further, in accordance with the present invention, an electrode set is provided. The electrode set comprises a plate element formed to include a recess therein, electrodes positioned on the plate element and cooperating to define an electrode array, and a reagent positioned on at least a portion of the electrodes. In addition, the recess circumscribes at least a portion of the electrode array.
In accordance with yet another aspect of the present invention a method of forming a biosensor is provided. The method comprises the steps of providing a plate element, forming at least one recess in the plate element, and applying a reagent onto the plate element to define a reaction zone. In addition, at least one recess circumscribes at least a portion of the reaction zone.
Additional features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention